Microwave cooking packages, consisting of microwave-transparent enclosures wherein the food rests on a microwave-transparent absorbent pad within the sealed enclosure are disclosed, for example in U.S. Pat. No. 4,865,854 and U.S. Pat. No. 4,873,101. In addition U.S. Pat. No. 5,096,722 describes an improved absorbent pad to be used within the packages described in the '854 and '101 patents. The improved pad has higher temperature resistance and sufficient microwave transparency to handle more severe cooking conditions. Other references describe multilayer cooking for example, U.S. Pat. No. 4,786,513, and special “blotters” or absorbent pads U.S. Pat. No. 4,720,410.
U.S. Pat. No. 5,096,722, mentioned above acknowledges the need for an absorbent pad totally free of finishing chemicals, microwave transparent and having a relatively high melting point (above 450° F.). It also describes a smooth pad face, totally free of finishes, consisting of a spunbonded polyester nonwoven attached to a needle-punched polyester staple grease-adsorbent batt. Other references mention lower melting materials for microwave cooking package pads such as polypropylene, poly-4-methyl-pentene-1. Such pads of lower melting materials can soften and conform to the surface of cooking and shrinking meats. The entire disclosures of each patent mentioned herein is hereby incorporated by reference.
It has now been discovered that during cooking excessive adhesion of food to the microwave cooking package materials of prior art systems can occur. Food adhesion can be problematic even with a system of the '722 patent despite its use of higher temperature-resistant and relatively chemical- and finish-free materials. Excessive food adhesion is particularly noteworthy when lean and heavy meats are microwave-cooked, and especially when the absorbent pad shrinks along with the cooked meats and/or conforms to the shrinking meat surface.